This invention relates to an apparatus for counting sheets such as bank notes and discriminating different kinds thereof.
In general, this type of apparatus is designed to count a number of bendable sheets, such as bank notes, of a particular kind while discriminating or detecting different kinds of bank notes intermingled among the particular kind of bank notes.
Conventionally, in this type of apparatus, as shown in FIG. 1, a stack of bendable sheets A, bank notes, for example, of a particular kind are placed on a holder 1 with their shorter edges in the vertical direction. The holder 1 is then rotated toward a rotary disk 2 disposed near the holder 1 so that the stack of bank notes A is held between the upright wall of the holder 1 and a support rod 3 disposed against the holder 1, and at the same time, one side surface of the stack of bank notes A comes into contact with one of a plurality of rotary suction heads 4 which are arranged in a circle on the disk 2. The suction head 4 suckingly attracts the outermost bank note A by means of a vacuum pump (not shown) while the suction heads 4 are rotated about their own axes and at the same time the disk is rotated about the axis thereof by means of a driving device (not shown). Thus, the bank notes A are attracted, one at a time, by the suction heads 4 and deflected away from the stack of bank notes A thereby making counts. At the same time, in order to discriminate different kinds of bank notes, which might be included among the stack of bank notes A placed on the holder 1, form the particular kind of bank notes, the upper corner portion (the shadowed portion in the Figure) of each bank note, at the time it is sucked onto the suction head 4 and deflected away from the stack of bank notes A, is subjected to optical detection by a discriminating system which comprises a light-projecting member 5 and a light-receiving member 6 thereby to optically detect or examine the height, i.e., the length of the shorter side, of the bank note.
In such prior art apparatus, however, there is a problem that, when a bank note is deflected away from the stack of bank notes A by the suction head 4, the deflected corner portion of this bank note, which is to be subjected to optical detection, often bends downward toward the stack of bank notes A on the holder 1. As a result, the bank note is detected to have less height, and accordingly this bank note is erroneously judged to be of a different sort.